The Right Ventricular Outflow Tract: The Road to Septal Pacing

Abstract

In this article, we will review the anatomy of the RVOT and discuss the importance of standard radiographic views and the 12-lead electrocardiogram in aiding lead placement. We will also describe a method utilizing a novel stylet shape, whereby a conventional active-fixation, stylet-driven lead can be easily and reliably deployed onto the RVOT septum.

Selective Site Pacing From the Right Ventricular Mid-Septum

“…18) Additionally, the anatomical accuracy for RV outflow tract is poor and several reports have used inconsistent pacing sites: RV outflow tract free wall or septum. [14][15][16] This has led to procedural difficulties and a risk of complications such as pericardial fluid. 19) The SSP procedure that we introduce in this study enabled safe and accurate positioning of a lead in the RV mid-septum without complications that require a surgical procedure.…”

“…[9][10][11] In SSP, His-bundle or para-His pacing 12,13) and a procedure where a ventricular lead is positioned in the RV outflow tract have been used. [14][15][16] The former involves technical difficulties, whereas the latter has produced unsatisfactory longterm effects and also poses a high risk of complications such as pericardial effusion. 17) In this study, we evaluated the efficacy and safety of SSP in patients in whom RV leads were positioned in the middle of the RV septum (mid-septum) and compared it with conventional RV apex pacing.…”

Feasibility and effect of para-right bundle branch pacing in patients with atrial fibrillation and complete atrioventricular block

“…However, because of the poor description of RVOT and the lacking of consistent anatomic designation, the pacing sites at RVOT in the published studies include a variety of pacing sites indeed, such as true outflow tract, mid-septum and anterior region above the apex. Therefore, the acute and chronic studies of RVOT pacing have produced conflicting results [17].…”

“…Traditionally, the right ventricular (RV) pacing leads have been fixed in the RV apex (RVA) [2]. Pacing from the RVA triggers a special wave of depolarization, which induces an aberrant ventricular activation and an elongation of ventricular activation time with consequent postponed activation of the left ventricular lateral wall [3]. Prolonged pacing from the RVA is associated with progressive left ventricular dysfunction, exacerbation of heart failure, atrial fibrillation, and an increased morbidity and mortality [4].…”

Changes in left ventricular global and regional longitudinal strain during right ventricular pacing

“…Appropriate positioning of the electrode was confirmed fluoroscopically at the time of the pacemaker implantation, before the baseline visit. Documentation of lead position was acquired in each patient using three standard projections: anterior-posterior, 40° left anterior oblique (LAO 40°), and 40° right anterior oblique (RAO 40°) views referring to the method described by Mond et al [11]. The LAO fluoroscopic view appears to be the most desirable method to determine RV septal positioning [12,13].…”